Qualidade do processo do sistema de irrigação por gotejamento com diferentes águas e declividade da linha lateral.

Abstract

Drip irrigation has as its main characteristic the distribution of water in a localized way, directly in the root system of the crop. Its physical characteristics of application allow to realize a uniform distribution of water and / or fertilizers, if the system is used for fertirrigation. Many researches propose the use of alternative water sources, such as wastewaters or effluents, seeking the reuse of nutrients with the input in the soil, post-treatment destination or because it is an abundant and perennial resource, an important characteristic especially for arid regions. The mechanisms of water application in drip irrigation are influenced by a number of factors, such as the quality of the water used and the design characteristics, among them the dripper and topographic type of the area. The objective of the research was to verify the quality of the irrigation with waters from alternative water sources, altering the slope of the lateral drip line. For the verification was used in addition to the coefficients of uniformity, the quality control charts, which is a statistical tool of use for monitoring the quality in processes. For the research was set up a bench of laboratory tests and for its use was suggested a methodology to gauge its capacity to obtain data. The obtained results showed that the bench can be used for drip test, preferably for pressures of 60 and 80 kPa, values ​​that did not obtain points out of control and maintained the randomness. The drip lateral lines presented a significant difference for the flow values ​​between the slope of the line and the application of water with parameters of varied quality, in this way it was verified that the water with inferior quality interferes in the flows of the drippers independent of the variation of pressure provided by the slope of the lateral line. The use of univariate or multivariate quality control statistics has been shown to be a sensitive tool to change flow values ​​and application uniformity, becoming an alternative to the large generation of automated monitoring data. With the use of this statistic, it was identified the capacity of the system to modify the average flow of the drippers uniformly, without changing the application coefficients.